Schnorkell and pre-cleaner
I fitted the Nugget Snorkel sealing kit, helps greatly in ensuring the air entering the filter box is only from the head of the snorkel as opposed to water/air from leaks in plumbing.
I also installed a Sy-Klone International pre-cleaner. I noticed that Nugget had one and it works very well in removing the dust prior to going down the snorkel.
I also removed the flow director from the entrance of the airbox as it greatly slowed the rate of air entering the airbox(this also reduced the amount of negative pressure and therefore slowed the Sy-Klone).
On Cape York trip it greatly reduced amount of dust in filter. There was still a tiny amount but much less than those who didn't use a pre-cleaner.